Dear R users, Does the results below make any sense? Can the the interval of the correlation coefficient be between *-1.0185* and -0.8265 at 95% confidence level? Liviu
> library(boot) > data(mtcars) > with(mtcars, cor.test(mpg, wt, met="spearman")) Spearman's rank correlation rho data: mpg and wt S = 10292, p-value = 1.488e-11 alternative hypothesis: true rho is not equal to 0 sample estimates: rho -0.88642 Warning message: In cor.test.default(mpg, wt, met = "spearman") : Cannot compute exact p-values with ties > corr.fun <- function(data, indices) { + data.samp <- data[indices,] # allows boot to select sample + tmp.corr <- with(data.samp, cor.test(mpg, wt, met="spearman")) + return(tmp.corr$estimate) + } > corr.boot <- boot(mtcars, corr.fun, R=1000) There were 50 or more warnings (use warnings() to see the first 50) > corr.boot ORDINARY NONPARAMETRIC BOOTSTRAP Call: boot(data = mtcars, statistic = corr.fun, R = 1000) Bootstrap Statistics : original bias std. error t1* -0.88642 0.012992 0.050042 > boot.ci(corr.boot, type="basic") BOOTSTRAP CONFIDENCE INTERVAL CALCULATIONS Based on 1000 bootstrap replicates CALL : boot.ci(boot.out = corr.boot, type = "basic") Intervals : Level Basic 95% (-1.0185, -0.8265 ) Calculations and Intervals on Original Scale -- Do you know how to read? http://www.alienetworks.com/srtest.cfm Do you know how to write? http://garbl.home.comcast.net/~garbl/stylemanual/e.htm#e-mail ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.